An image forming apparatus conveys a sheet-like medium (hereinafter collectively referred to as “sheet”) such as paper and forms an image on the sheet. The image forming apparatus includes a plurality of rollers arranged along a conveyance path. The plurality of rollers in may convey the sheet in a deflected state.
For example, the image forming apparatus includes a conveyance roller and a register roller. The conveyance roller conveys the sheet conveyed from a sheet housing section towards the register roller. When the front end of the sheet reaches the register roller, the register roller is stopped. The conveyance roller continues conveying the sheet after the sheet reaches the register roller. In this way, the front end of the sheet is pressed against the register roller. Then, the rotation of the conveyance roller is stopped.
The sheet may become inclined in the conveyance direction during the process of being picked up from the sheet housing section or the process of being conveyed along the conveyance path. In such a case, the sheet nipped by the conveyance roller is inclined, meaning that the front end of the sheet conveyed towards the register roller is not parallel to the rotation axis of the register roller.
However, the front end of the sheet becomes parallel to the rotation axis of the register roller when the front end of the sheet is pressed against the register roller. However, the sheet nipped by the conveyance roller is still in the inclined state. As a result, the deflection amount of the sheet is not uniform at the left and right side of the sheet in the conveyance direction. In this non-uniformly deflected state, the sheet is drawn in by the register roller. Then the non-uniformly deflected sheet is compressed by the register roller, which may cause flaws such as a wrinkle in the sheet.